(<pre> shouldn't be used here. Use <p> to start paragraphs, <c>..</c> around code, data and outputs)

Are you saying the following is no good for some reason?

sub trap_signals {
  local $SIG{CHLD} = \&handler;
  :
}
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It seems quite odd to set $SIG{CHLD} in a sub if you want it to have a global effect. But let's say it is a big init function, then you could either silence the critic (since the global effect is desired) or change

sub init {
   $SIG{CHLD} = ...;
   ... init code ...
}

{
   init()
   ... main code ...
}
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to

sub main {
   ... main code ...
}

{
   local $SIG{CHLD} = ...;
   ... init code ...
   main();
}
[download]